Cargo update

Cargo.toml

@@ -48,9 +48,9 @@ env_logger = "0.6"
 getopts = "0.2"
 derive-new = "0.5"
 cargo_metadata = "0.7"
-rustc-ap-rustc_target = "407.0.0"
-rustc-ap-syntax = "407.0.0"
-rustc-ap-syntax_pos = "407.0.0"
+rustc-ap-rustc_target = "486.0.0"
+rustc-ap-syntax = "486.0.0"
+rustc-ap-syntax_pos = "486.0.0"
 failure = "0.1.3"
 bytecount = "0.5"
 unicode-width = "0.1.5"

src/attr.rs

@@ -2,6 +2,7 @@
 
 use syntax::ast;
 use syntax::source_map::{BytePos, Span, DUMMY_SP};
+use syntax::symbol::sym;
 
 use self::doc_comment::DocCommentFormatter;
 use crate::comment::{contains_comment, rewrite_doc_comment, CommentStyle};
@@ -52,15 +53,15 @@ pub(crate) fn filter_inline_attrs(
 }
 
 fn is_derive(attr: &ast::Attribute) -> bool {
-    attr.check_name("derive")
+    attr.check_name(sym::derive)
 }
 
 /// Returns the arguments of `#[derive(...)]`.
 fn get_derive_spans<'a>(attr: &'a ast::Attribute) -> Option<impl Iterator<Item = Span> + 'a> {
     attr.meta_item_list().map(|meta_item_list| {
         meta_item_list
             .into_iter()
-            .map(|nested_meta_item| nested_meta_item.span)
+            .map(|nested_meta_item| nested_meta_item.span())
     })
 }
 
@@ -189,9 +190,9 @@ fn rewrite_initial_doc_comments(
 
 impl Rewrite for ast::NestedMetaItem {
     fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
-        match self.node {
-            ast::NestedMetaItemKind::MetaItem(ref meta_item) => meta_item.rewrite(context, shape),
-            ast::NestedMetaItemKind::Literal(ref l) => rewrite_literal(context, l, shape),
+        match self {
+            ast::NestedMetaItem::MetaItem(ref meta_item) => meta_item.rewrite(context, shape),
+            ast::NestedMetaItem::Literal(ref l) => rewrite_literal(context, l, shape),
         }
     }
 }
@@ -219,10 +220,10 @@ impl Rewrite for ast::MetaItem {
     fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
         Some(match self.node {
             ast::MetaItemKind::Word => {
-                rewrite_path(context, PathContext::Type, None, &self.ident, shape)?
+                rewrite_path(context, PathContext::Type, None, &self.path, shape)?
             }
             ast::MetaItemKind::List(ref list) => {
-                let path = rewrite_path(context, PathContext::Type, None, &self.ident, shape)?;
+                let path = rewrite_path(context, PathContext::Type, None, &self.path, shape)?;
                 let has_trailing_comma = crate::expr::span_ends_with_comma(context, self.span);
                 overflow::rewrite_with_parens(
                     context,
@@ -240,7 +241,7 @@ impl Rewrite for ast::MetaItem {
                 )?
             }
             ast::MetaItemKind::NameValue(ref literal) => {
-                let path = rewrite_path(context, PathContext::Type, None, &self.ident, shape)?;
+                let path = rewrite_path(context, PathContext::Type, None, &self.path, shape)?;
                 // 3 = ` = `
                 let lit_shape = shape.shrink_left(path.len() + 3)?;
                 // `rewrite_literal` returns `None` when `literal` exceeds max
@@ -326,15 +327,16 @@ impl Rewrite for ast::Attribute {
 
             if let Some(ref meta) = self.meta() {
                 // This attribute is possibly a doc attribute needing normalization to a doc comment
-                if context.config.normalize_doc_attributes() && meta.check_name("doc") {
+                if context.config.normalize_doc_attributes() && meta.check_name(sym::doc) {
                     if let Some(ref literal) = meta.value_str() {
                         let comment_style = match self.style {
                             ast::AttrStyle::Inner => CommentStyle::Doc,
                             ast::AttrStyle::Outer => CommentStyle::TripleSlash,
                         };
 
+                        let literal_str = literal.as_str();
                         let doc_comment_formatter =
-                            DocCommentFormatter::new(literal.as_str().get(), comment_style);
+                            DocCommentFormatter::new(literal_str.get(), comment_style);
                         let doc_comment = format!("{}", doc_comment_formatter);
                         return rewrite_doc_comment(
                             &doc_comment,

src/chains.rs

@@ -118,6 +118,7 @@ enum ChainItemKind {
     ),
     StructField(ast::Ident),
     TupleField(ast::Ident, bool),
+    Await,
     Comment(String, CommentPosition),
 }
 
@@ -128,6 +129,7 @@ impl ChainItemKind {
             ChainItemKind::MethodCall(..)
             | ChainItemKind::StructField(..)
             | ChainItemKind::TupleField(..)
+            | ChainItemKind::Await
             | ChainItemKind::Comment(..) => false,
         }
     }
@@ -166,6 +168,10 @@ impl ChainItemKind {
                 let span = mk_sp(nested.span.hi(), field.span.hi());
                 (kind, span)
             }
+            ast::ExprKind::Await(_, ref nested) => {
+                let span = mk_sp(nested.span.hi(), expr.span.hi());
+                (ChainItemKind::Await, span)
+            }
             _ => return (ChainItemKind::Parent(expr.clone()), expr.span),
         };
 
@@ -189,6 +195,7 @@ impl Rewrite for ChainItem {
                 if nested { " " } else { "" },
                 rewrite_ident(context, ident)
             ),
+            ChainItemKind::Await => ".await".to_owned(),
             ChainItemKind::Comment(ref comment, _) => {
                 rewrite_comment(comment, false, shape, context.config)?
             }
@@ -387,9 +394,9 @@ impl Chain {
             ast::ExprKind::MethodCall(_, ref expressions) => {
                 Some(Self::convert_try(&expressions[0], context))
             }
-            ast::ExprKind::Field(ref subexpr, _) | ast::ExprKind::Try(ref subexpr) => {
-                Some(Self::convert_try(subexpr, context))
-            }
+            ast::ExprKind::Field(ref subexpr, _)
+            | ast::ExprKind::Try(ref subexpr)
+            | ast::ExprKind::Await(_, ref subexpr) => Some(Self::convert_try(subexpr, context)),
             _ => None,
         }
     }

src/closures.rs

@@ -1,4 +1,3 @@
-use syntax::parse::classify;
 use syntax::source_map::Span;
 use syntax::{ast, ptr};
 
@@ -25,7 +24,7 @@ use crate::utils::{last_line_width, left_most_sub_expr, stmt_expr, NodeIdExt};
 
 pub(crate) fn rewrite_closure(
     capture: ast::CaptureBy,
-    asyncness: ast::IsAsync,
+    is_async: &ast::IsAsync,
     movability: ast::Movability,
     fn_decl: &ast::FnDecl,
     body: &ast::Expr,
@@ -36,7 +35,7 @@ pub(crate) fn rewrite_closure(
     debug!("rewrite_closure {:?}", body);
 
     let (prefix, extra_offset) = rewrite_closure_fn_decl(
-        capture, asyncness, movability, fn_decl, body, span, context, shape,
+        capture, is_async, movability, fn_decl, body, span, context, shape,
     )?;
     // 1 = space between `|...|` and body.
     let body_shape = shape.offset_left(extra_offset)?;
@@ -134,7 +133,7 @@ fn rewrite_closure_with_block(
     shape: Shape,
 ) -> Option<String> {
     let left_most = left_most_sub_expr(body);
-    let veto_block = veto_block(body) && !classify::expr_requires_semi_to_be_stmt(left_most);
+    let veto_block = veto_block(body) && !expr_requires_semi_to_be_stmt(left_most);
     if veto_block {
         return None;
     }
@@ -207,7 +206,7 @@ fn rewrite_closure_block(
 // Return type is (prefix, extra_offset)
 fn rewrite_closure_fn_decl(
     capture: ast::CaptureBy,
-    asyncness: ast::IsAsync,
+    asyncness: &ast::IsAsync,
     movability: ast::Movability,
     fn_decl: &ast::FnDecl,
     body: &ast::Expr,
@@ -291,7 +290,7 @@ pub(crate) fn rewrite_last_closure(
     expr: &ast::Expr,
     shape: Shape,
 ) -> Option<String> {
-    if let ast::ExprKind::Closure(capture, asyncness, movability, ref fn_decl, ref body, _) =
+    if let ast::ExprKind::Closure(capture, ref is_async, movability, ref fn_decl, ref body, _) =
         expr.node
     {
         let body = match body.node {
@@ -305,7 +304,7 @@ pub(crate) fn rewrite_last_closure(
             _ => body,
         };
         let (prefix, extra_offset) = rewrite_closure_fn_decl(
-            capture, asyncness, movability, fn_decl, body, expr.span, context, shape,
+            capture, is_async, movability, fn_decl, body, expr.span, context, shape,
         )?;
         // If the closure goes multi line before its body, do not overflow the closure.
         if prefix.contains('\n') {
@@ -387,3 +386,26 @@ fn is_block_closure_forced_inner(expr: &ast::Expr, version: Version) -> bool {
         _ => false,
     }
 }
+
+/// Does this expression require a semicolon to be treated
+/// as a statement? The negation of this: 'can this expression
+/// be used as a statement without a semicolon' -- is used
+/// as an early-bail-out in the parser so that, for instance,
+///     if true {...} else {...}
+///      |x| 5
+/// isn't parsed as (if true {...} else {...} | x) | 5
+// From https://github.com/rust-lang/rust/blob/master/src/libsyntax/parse/classify.rs.
+fn expr_requires_semi_to_be_stmt(e: &ast::Expr) -> bool {
+    match e.node {
+        ast::ExprKind::If(..)
+        | ast::ExprKind::IfLet(..)
+        | ast::ExprKind::Match(..)
+        | ast::ExprKind::Block(..)
+        | ast::ExprKind::While(..)
+        | ast::ExprKind::WhileLet(..)
+        | ast::ExprKind::Loop(..)
+        | ast::ExprKind::ForLoop(..)
+        | ast::ExprKind::TryBlock(..) => false,
+        _ => true,
+    }
+}

src/expr.rs

@@ -1,5 +1,6 @@
 use std::borrow::Cow;
 use std::cmp::min;
+use std::iter;
 
 use itertools::Itertools;
 use syntax::parse::token::DelimToken;
@@ -183,9 +184,9 @@ pub(crate) fn format_expr(
                 Some("yield".to_string())
             }
         }
-        ast::ExprKind::Closure(capture, asyncness, movability, ref fn_decl, ref body, _) => {
+        ast::ExprKind::Closure(capture, ref is_async, movability, ref fn_decl, ref body, _) => {
             closures::rewrite_closure(
-                capture, asyncness, movability, fn_decl, body, expr.span, context, shape,
+                capture, is_async, movability, fn_decl, body, expr.span, context, shape,
             )
         }
         ast::ExprKind::Try(..) | ast::ExprKind::Field(..) | ast::ExprKind::MethodCall(..) => {
@@ -335,10 +336,6 @@ pub(crate) fn format_expr(
                 ))
             }
         }
-        ast::ExprKind::ObsoleteInPlace(ref lhs, ref rhs) => lhs
-            .rewrite(context, shape)
-            .map(|s| s + " <-")
-            .and_then(|lhs| rewrite_assign_rhs(context, lhs, &**rhs, shape)),
         ast::ExprKind::Async(capture_by, _node_id, ref block) => {
             let mover = if capture_by == ast::CaptureBy::Value {
                 "move "
@@ -371,6 +368,18 @@ pub(crate) fn format_expr(
                 ))
             }
         }
+        ast::ExprKind::Await(ast::AwaitOrigin::FieldLike, _) => rewrite_chain(expr, context, shape),
+        ast::ExprKind::Await(ast::AwaitOrigin::MacroLike, ref nested) => {
+            overflow::rewrite_with_parens(
+                context,
+                "await!",
+                iter::once(nested),
+                shape,
+                expr.span,
+                context.config.max_width(),
+                None,
+            )
+        }
         ast::ExprKind::Err => None,
     };
 

src/formatting.rs

@@ -33,11 +33,7 @@ impl<'b, T: Write + 'b> Session<'b, T> {
             return Err(ErrorKind::VersionMismatch);
         }
 
-        syntax::with_globals(|| {
-            syntax_pos::hygiene::set_default_edition(
-                self.config.edition().to_libsyntax_pos_edition(),
-            );
-
+        syntax::with_globals(self.config.edition().to_libsyntax_pos_edition(), || {
             if self.config.disable_all_formatting() {
                 // When the input is from stdin, echo back the input.
                 if let Input::Text(ref buf) = input {
@@ -687,7 +683,7 @@ fn parse_crate(
 struct SilentEmitter;
 
 impl Emitter for SilentEmitter {
-    fn emit(&mut self, _db: &DiagnosticBuilder<'_>) {}
+    fn emit_diagnostic(&mut self, _db: &DiagnosticBuilder<'_>) {}
 }
 
 fn silent_emitter() -> Box<SilentEmitter> {

src/imports.rs

@@ -4,6 +4,7 @@ use std::fmt;
 
 use syntax::ast::{self, UseTreeKind};
 use syntax::source_map::{self, BytePos, Span, DUMMY_SP};
+use syntax::symbol::sym;
 
 use crate::comment::combine_strs_with_missing_comments;
 use crate::config::lists::*;
@@ -249,7 +250,7 @@ impl UseTree {
         match self.attrs {
             Some(ref attrs) if !attrs.is_empty() => {
                 let attr_str = attrs.rewrite(context, shape)?;
-                let lo = attrs.last().as_ref()?.span().hi();
+                let lo = attrs.last().as_ref()?.span.hi();
                 let hi = self.span.lo();
                 let span = mk_sp(lo, hi);
 
@@ -395,7 +396,7 @@ impl UseTree {
                     rewrite_ident(context, path_to_imported_ident(&a.prefix)).to_owned()
                 };
                 let alias = rename.and_then(|ident| {
-                    if ident.name == "_" {
+                    if ident.name == sym::underscore_imports {
                         // for impl-only-use
                         Some("_".to_owned())
                     } else if ident == path_to_imported_ident(&a.prefix) {